Packaged semiconductor devices containing multiple semiconductor die provide high device density. In addition, packaged semiconductor devices containing multiple semiconductor die can provide increased functionality and performance.
Packaged semiconductor devices containing multiple semiconductor die typically include a first semiconductor die that is attached to a package substrate. Bonding pads are disposed around the periphery of the top surface of the first semiconductor die. Wire bonds electrically connect to the bonding pads on the first semiconductor die and electrically connect to corresponding bonding pads located on the package substrate. The spacer is then attached to the center of the top surface of the first semiconductor die.
The second semiconductor die is attached to the spacer. Bonding pads disposed on the top surface of the second semiconductor die are then electrically connected to bonding pads on the package substrate using wire bonds. Encapsulant is then applied so as to cover the semiconductor die and all of the wire bonds.
The manufacturing process for forming packaged semiconductor devices containing multiple semiconductor die is expensive. More particularly, spacers add cost to the manufacturing process. In addition, the spacer must be precisely placed so as to prevent damage to wire bonds.
Also, it is difficult to apply encapsulant such that the encapsulant will completely fill the areas surrounding the spacer. Often, air is trapped under the second semiconductor die in the areas surrounding the spacer. This causes voids within the encapsulant in the areas surrounding the spacer. This leads to a packaged semiconductor device having reduced structural integrity. Also, the voids can trap moisture, leading to reliability problems.
What is needed is a packaged semiconductor device and a method for forming a packaged semiconductor device having improved structural integrity and reliability. Also, a method and apparatus is needed that meets the above need while reducing manufacturing cost. The present invention meets the above needs.